Preparation and Properties of ionic liquid
|School||Kunming University of Science and Technology|
|Keywords||Ionic liquid Amide Microwave synthesis Physicochemical properties Electrochemistry|
Ionic liquid is a new green solvent, which is attracted by most reaserchsers. Many studies about the traditional imidazole and pyridine based ionic liquids have been reported. It is found that acetamide can react with zinc chloride to obtian the deep eutectic based ionic liquid, when a new kind of room temperature ionic liquid is prepeared. Compared with these conventional ionic liquids, this ionic liquid has many attractive properties, for instance, simple synthetic method, preferable physicochemical properties, low cost and relatively fewer side effects. The major research results are drawn as follows:This deep eutectic based ionic liquid can be synthesized by simplely heating the mixture of C2H5ON and ZnCl2 in some appropriate proportions and is characterized by infrared spectrum.When x(ZnCl2) is 0.05～0.5, the freezing point is observed below 78℃. The phase diagram of the C2H5ON-ZnCl2 ionic liquid was plotted by cooling curve method. In the case of 0.25, C2H5ON and ZnCl2 can fully form the target product, and the system has the lowest freezing point of 8℃.The viscosity of C2H5ON-ZnCl2 ionic liquid is 65.1mPa·s, when x(ZnCl2) is 0.25 at the temperature of 70℃.The physicochemical properties such as conductivity and activation energy for conductivity of C2H5ON-ZnCl2 ionic liquid is 6312μS/cm and 12.47kJ·mol-1, respectively, when x(ZnCl2) is 0.25 at the temperature of 70℃.The conductivity of C2H5ON-ZnCl2 ionic liquids with different components increases with the increase in the temperatrue and the percentage of acetamide at a given temperature, while, the viscosity of these ionic liquids decreases with increasing temperature. The electrochemical window of C2H5ON-ZnCl2 ionic liquid is 2V. The cyclic voltammetry curves obtained with different components show that the cathodic reduction is a quasi-reversible prcess with diffusion controlled.In addition, this paper also gives an innovative method for microwave synthesis of BMIC. The main work is as follows:BMIC is synthesized by microwave method. The optimum reaction conditions are at the temperature of 72℃with the reaction power of 300W during intermittent heating reaction for 120 min. The limited yield for the microwave synthesis is 50%. The product synthesized by microwave is confirmed by IR spectroscopy.There are many advantages of the microwave method as compared to these tradional synthetic methods such as, no addition of organic solvents in the synthesis of ionic liquids, direct isolation of BMIC from the products with stewing, short reaction time and good quality of products.